Design Guide

Intel 855GM/GME Chipset Based System Power Delivery Guidelines
R
272 Intel
®
855GM/855GME Chipset Platform Design Guide
Table 114. Analog Supply Filter Requirements
Required
GMCH
Filters
Config Rdamp Rdamp
location
L Cbulk Chigh
VCCASM V1.5S None N/A 1210 1.0 µH
DCRmax 0.169
Ωs
100 µF 0603 0.1 µF X5R
VCCQSM V2.5S 1 Ω In series with
C
bulk
0805 0.68 µH
DCRmax 0.80 Ωs
1206 4.7 µF
X5R
0603 0.1 µF X5R
VCCAHPLL V_1.2S
2
V_1.35S
3
None N/A None 0603 0.1 µF X5R
VCCADPLLA
1
V_1.2S
2
V_1.35S
3
1
Ω In series with
inductor
0805 0.10 µH 220uF 0603 0.1 µF X5R
VCCADPLLB
1
V_1.2S
2
V_1.35S
3
1
Ω In series with
inductor
0805 0.10 µH 220 µF 0603 0.1 µF X5R
VCCADAC
1
V1.5S None N/A None None 0603 0.1 µF X5R
0603 0.01 µF
X5R
VCCAGPLL V_1.2S
2
V_1.35S
3
None N/A None None 0603 0.1 µF X5R
VCCALVDS
1
V1.5S None N/A None None 0603 0.1 µF X5R
0603 0.01 µF
X5R
NOTES:
1. Not required when using 855GME platform design with external graphics only.
2. For 855GM platform
3. For 855GME platform
13.5.4. ICH4-M Decoupling / Power Delivery Guidelines
13.5.4.1. ICH4-M Decoupling
The ICH4-M is capable of generating large current swings when switching between logic high and logic
low. This condition could cause the component voltage rails to drop below specified limits. To avoid
this type of situation, ensure that the appropriate amount of decoupling capacitance is added in parallel
to the voltage input pins. Intel recommends that the developer use the amount of high frequency
decoupling capacitors specified in table below to ensure that component maintains stable supply
voltages. Low frequency decoupling is dependent on layout and system power supply design.